1. Technical Field
The present invention relates to a seat back device that is placed on a rear side of a vehicle cabin.
2. Related Art
Among seat back devices, there are seat back devices in which the angle of a cushion pad that supports the lumbar region of a passenger can be adjusted (e.g., see Japanese Examined Utility Model Application No. H4-50846). These seat back devices have the advantage that comfort is improved and passenger fatigue can be alleviated by adjusting the angle of the cushion pad.
Meanwhile, among seat back devices that are placed on a rear side of a vehicle cabin, there are seat back devices in which the vehicle cabin and a trunk room are made communicable by forwardly collapsing part of the seat back (a so-called trunk-through function). Seat back devices equipped with the trunk-through function have the advantage that luggage can be put into and taken out from between the vehicle cabin and the trunk room and long items of luggage can be accommodated in the vehicle.
Consequently, it is preferable for seat back devices that are placed on the rear side of the vehicle cabin to be equipped with both advantages.